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101.
目的了解广州地区2002年淋球菌对抗生素的耐药性及产青霉素酶淋球菌(PPNG)和高水平耐四环素淋球菌(TRNG)的流行状况。方法用琼脂稀释法测定四环素、壮观霉素、头孢三嗪和环丙沙星4种抗生素对100株淋球菌的最低抑菌浓度(MIC)及用纸片碘量法检测β-内酰胺酶。结果100株淋球菌检出PPNG 15株(15%)、TRNG 28株(28%),环丙沙星耐药率高达98%,高度耐药株(MIC≥16 mg/L)32株(32%),未发现对头孢三嗪、壮观霉素的耐药菌株,但头孢三嗪的敏感性有所下降。结论目前广州地区流行的淋球菌菌珠耐药状况仍然严重,尤以环丙沙星为甚,但对壮观霉素和头孢三嗪仍较敏感。此外,有必要持续监测球菌的耐药性。  相似文献   
102.
During liver transplantation for hepatocellular carcinoma (HCC) patients, HCC could theoretically be introduced into the systemic circulation when salvaged blood is used with an autotransfusion device. Several reports have shown that some types of leukocyte depletion filters (LDFs) could completely reduce the risk for reintroducing some types of tumor cells. In this study, we tested the ability of the LDF (RCEZ1T, Pall Biomedical Co, NY, USA) to reduce the risk for reintroducing HCC cells in vitro by using a very sensitive detection method. We divided the test group into 6 groups: group I was 10 cells, group II was 20 cells, group III was 2 x 10(3) cells, group IV was 2 x 10(5) cells, group V was 2 x 10(6) cells, and group VI was 2 x 10(7) cells. The counted cells in 200 mL saline were passed through the RCEZ1T using the force of gravity. To identify the presence of cells, the pellet was resuspended, and polymerase chain reaction (PCR) was performed. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a housekeeping gene, was used as a primer. In groups I and II, the HCC cells were completely filtered in all experiments. However, in groups III, IV, and V, the HCC cells were not completely filtered in a few of the repeated experiments, with the unfiltered rate of tumor cells being between 8% and 20%. In group VI, the HCC cells were not completely filtered in all the repeated experiments. In conclusion, the RCEZ1T filter markedly reduced the risk for reintroduction of HCC cells. However, at high HCC cell load the filter cannot completely remove all the tumor cells. Further studies are required to assess the impact in clinical settings.  相似文献   
103.
简要介绍西门子SOMATOM CT高压发生器的工作原理,并着重分析了高压63A熔断丝炸裂故障原因及其判断与排除方法。文章指出了在检修高压发生器的过程中特别要注意的事项。  相似文献   
104.
Q P Ma  Y S Shi  J S Han 《Brain research》1992,583(1-2):292-295
Previous findings from this laboratory with the intracerebral microinjection technique suggested that the periaqueductal gray (PAG), nucleus accumbens, and habenula might constitute a unidirectional loop to play their roles in pain modulation. In the present study we demonstrate that intra-habenular injection of naloxone antagonizes the analgesia elicited by morphine injected into the periaqueductal gray (PAG) and that intra-accumbens injection of naloxone is capable of attenuating the analgesic effects of morphine injected into the habenula. These results indicate that the relationships between these nuclei may be more complex than the putative unidirectional loop.  相似文献   
105.
卡那霉素链霉菌温和性噬菌体SKJ1DNA上有2个AvaI和SmaI酶切位点,8个SalI位点,7个EcoRI位点及12个BamHI位点,经酶切后用1%琼脂糖凝胶电泳测定SKJ1DNA大小为60.7kb。用单酶切,双酶切及片段酶切分析,得到SKJ1DNA的AvaI、SmaI、EcoRI、SalI酶切图谱及BamI1的部分酶切图谱,证明AvaI和SmaI在SKJ1DNA上具有相同酶切位点,并经过酶切结  相似文献   
106.
观测了100例成年尸体胃底、贲门及食管区静脉。结果显示:胃左、右静脉的出现率是96%和92%,胃小弯侧的静脉分布可归纳为5型:胃左静脉型、胃右静脉型、胃左静脉优势型、胃右静脉优势型和胃左右静脉均衡型。胃后静脉出现率为73.6%,胃左静脉与左膈下静脉间有相对恒定的吻合,此种情况占48%。在此基础上作者于1976年3月至1992年3月对52例因门脉高压症大出血患者行经胸门奇静脉断流术,急症手术死亡率为4.9%,急症手术止血率为92.6%,远期再出血率为11.4%。作者认为彻底断流的关键是识别胃小弯侧静脉分型、胃左静脉汇入部位及属支变化;胃后静脉及门腔吻合。阐述了经胸门奇静脉断流的优越性。  相似文献   
107.
对食管癌高发区粮食中分离的互隔交链孢霉的毒素交链孢酚单甲醚(AME)在大鼠、小鼠体内的分布进行研究。给动物腹腔内注射氚标记的交链孢酚单甲醚(~3H-AME),然后在不同时间测各脏器的放射性。结果表明:在所测9个脏器中,2h肝脏含量最高,食管下段在大小鼠分别居第四和第三。但大小鼠分别在72、24h则以食管下段最高,说明AME及其代谢物在此清除较慢,即对其有较高的亲和力。  相似文献   
108.
D Z Shi 《中华妇产科杂志》1992,27(2):70-2, 123
To investigate the relationship between intrauterine infection and IUGR, the following studies have been carried out: (1) measurement of specific antibodies of Toxoplasma (Toxo) and Cytomegalovirus (CMV) in the umbilical serum samples from 30 cases of IUGR with 26 normal newborn infants as controls; (2) follow-up exam on 14 positive cases in 17-25 months. The results showed that in 30 IUGR cases 14 were found to have Toxo and CMV infection, with an incidence significantly higher than that in the control group. One third of the infected patients were found to have retarded growth afterbirth and 63.63% of them appeared to have an increase in BAEP. This suggested that regular follow-up is indicated in these cases.  相似文献   
109.
For investigating the effect of acupuncture on ischemic arrhythmia and its mech-anism, adult albino rats with ligated anterior descending branch of coronary artery as experimentalmodel were treated with or without acupuncture, and others with imitative operation but without bothcoronary artery ligation and acupuncture treatment were used as control. It was found in acupuncturegroup that the fibrillation-liability of ischemic myocardium was efficiently decreased, the affinity ofAch-M receptors on membranes of ischemic myocardium was markedly increased, and the tolerance ofischemic myocardium to atropine was elevated in the experiment of atropine inducing fibrillation.These results indicate that acupuncture may play a therapeutic role on ischemic arrhythmia throughactivating the activity of muscarine-like receptors of cholinergic nervous system.  相似文献   
110.
目的 研究彩色多普勒超声诊断房间隔缺损(ASD)的准确性。方法 回顾性分析经手术证实的64例ASD患者的超声检查结果并和手术结果对照。结果 64例患者中有1例三房心合并房间隔缺损畸形,1例合并右下肺静脉异位引流漏诊,术前超声正确诊断63例,定性诊断准确率达98.4%,有1例混合型定位不准确,定位准确率在98.4%,而且64例患者中超声检查结果显示在无合并其他畸形时房间缺损大小与右心系统扩大及肺动脉扩张呈正相关关系。结论 ASD是以右室容量超负荷为特征,彩色多普勒超声是诊断房间隔缺损的首选检查方法,并具有较高的准确性。  相似文献   
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